Liquid-peed system



f1.1.. smKEs. LIQUID FEED sYsTM.

APPLICATION FiLED NOV. 29, 1916.

f3 l 999 l 3 Patented Gut. 2S, 1919.

CHARLES L. STOKES, OF LOS ANGELES, CALIFORNIA.

LIQUID-FEED SYSTEM.

Specification of Letters Patent.

Patented Oct. 28, 1919.

Application led Novembei` 29, 1916. Serial No. 134,137.

T all whom it may concern.'

Be it known that I, CHARLES L. S'roKEs, a citizen of the United States, residing at Los Angeles, in the county of Los Angeles, State of California, have invented new and useful Improvements in Liquid-Feed Systenis, of which the following is a specifica- .the column offuel being lifted.

tion.

This invention relates to systems for feeding or lifting liquids, and, 1n its more pars ticular phase, hereinafter described, relates to systems for feeding or lifting liquid fuel for internal combustion engines of any type.

This invention has particularly to do with improvements upon the system shown and described in my applications S. Nos. 91,303; 120,069 and 124,473; led April 15, 1916, September 14, 1916, and October 9, 1916, res ectively; and this invention has for an o ject the provision of'ineans for increasing the efficiency of lifting the liquid fuel, both under normal conditions and under extraordinary conditions, as when an automobile is ascending or descending a steep grade.

In systems of vthe character herein described, arid described in my co-pending applications, it will be noted that the service reservoir, to which the liquid fuel is lifted by suction, is in permanent communication with the atmosphere; that is, communication with the atmosphere is never cut olf by any positive means. I make this atmospheric communication in such a manner as to not only supply atmospheric pressure to the surface of the liquid in the service 'res` ervoir during the periods when suction is not being applied; but also to apply air to So that, when the fuel is being lifted into the service reservoir, the air 'from atmosphere passes into the reservoir mixed with the fuel being raised. Itis a particular object of this present invention to provide improved means foi admitting said air in such ya manner' as to increase the eiliciency of the lifting opera air inlet performs its other function, as hereinafter described. These objects, and other objects which will hereinafter appear, are accomplished by means of m device, of which the following described orm is typical.` l

I referto the laccompanying drawings in A which: Figure 1 is a diagram .showing the '55 various .operative parts offmy system, and showing their relations and connections;

Fig. 2 is an enlarged detail section of the connection to the main fuel tank; Fig. 3 is an enlarged detailed section showing the means of y.admitting atmosphere to the lifting line and to the service reservoir; Fig. 4 is an enlarged' detail section of the service reservoir; and Fig. 5 is an enlarged detail section showing a modified' structure in which the service reservoir and carbureter are combined as a unit.

In the drawings the fuelv tank is shown at 10 yat a level lower than the carbureter 11 fed by the liquid fi'om the tank. This tank has the usual filling plug at 12 with ail-air inlet to apply atmospheric pressure to the liquid in the tank. The lifting pipe 13 connects into a fitting 14 which has a liquid passage 15 communicating with the tank and has also an air nozzle 16 controlled by a needle valve 17 to admit air into liquid flowing from the tank'into pipe 13. The air is drawn through the pipe 18, whose upper end is above the liquid level in tank 10. The amountof Iair admitted at nozzle 16 may be regulated or completely shut olf by valve 17. The lifting pipe 13 1s provided in its vertical portion with an interior air tube 20.

T his air tube is open at itsupper end at 21 to atmosphere and may be provided with an upwardly closing check valve 22 operated by a float 23 to close olf communication to atmosphere in ease the tank 10 should rise Avery high. This valve, however, is an emergency means. Normally, the upper end 21.0f tube 20 is above the liquid level in tank 10 so that no liquid can flow out. In fact` the uppermost perforation 24 in the air tube (which is on or about thelevel denoted 24a in Fig. 1) .is above Iany ordinary level of fuel in tank 10, while, at the saine time, it is below the ordinary level of the fuel in the service reservoir 25. This air ltube 20 is preferably of small dimensions. For instance, while lifting tube 13 may be 1 inside diameter, the Iair tube will probably be only about inside diameter and the perforations 24 are of about the size made by a No.V 64 drill. The lower endof tube 20 may either be closed, or a similarhole made at its lower end. It will be seen that although the uppermost hole 24 is normally above the liquid level, certain of the holes 24 are below the liquid level. It is only necessary for the operation of. my system, that the uppermost hole 24 be above the liquid level; but this does not mean that all the other holes must be below the normal level of liquid in tank 10.

The pipe 13 leads to the top of the service reservoir 25 and discharges into that reservoir through the cover 30 and through a nipple or baille 31 and strainer 31a extending intothe reservoir beneath the cover; this bathe being for the purpose of preventing the mixed air and liquid being drawn immediately to the suction port 32 before the air and liquid can separate. The suction pipe 33 extends from the intake manifold 34 of the engine (at a point above the throttle valve 35) to the suction port 32 of service reservoir 25. A valve 36 is adapted to close the port 32 by upward movement; and this valve is loosely mounted upon a lever 37 pivoted at 38 to a wall of the service reservoir and connecting at its end with float 39. This float is preferably somewhat weighted (as compared with the weight of ordinary floats of this character) so that its weight is sufficient to pull the valve 36 down against the suction tending to keep it up, when the liquid level in reservoir 25 has fallen so that the liquid support of the float it partially withdrawn. From the lower part of the reservoir "25 the liquid fuel passes out through pipe 40 tothe carbureter 11, passing the upwardly closing check valve 41, provided for the purpose of keeping the fuel inthe carburetor from being sucked back into the reservoir 25 when suction is applied to the reservoir. The valve 41 may be placed at the carbureter and seated by gravity. p

YWhen the service reservoir is full of liquid the float 39 moves up to the position shown and moves the valve 36 to close suction port 32. The closure of this suction port prevents further application' of suction to the reservoir. The gradual liow of liquid out of the reservoir to the carburetor lowers the liquid level in the reservoir and takesaway the liquid support of float 39. When the liquid level has fallen to such an extent that the unsupported weight of the float is sufcient to overcome the suction tending to support valve 36, then the float will fall, carrying valve 36 with it and suction will be reapplied to the upper part lof the reservoir. In an actual apparatus the arrangement is made such thatthe liquid level in the reservoir falls 'by about one quarter of an inch before the valve 36 is moved downwardly.

Suction being applied to the reservoir is, of course, also applied to pipe 13. The liquid from tank 10 normally stands up to a height depending upon the4 amount of liquid inthe tank; but the uppermost air port 24 is always higher than the normal liquid level. Suction applied to pipe 13 will immediately begin to'draw air through all the air ports 24 that are uncovered; but the amount of air introducedthrough these lports is insufiicient to break the suction. The fuel, therefore, begins to rise in pipe 13 and, after passing any port- ,24, this fuel is intermingled with the air drawn through the port. The valve 17, at the lower end of pipe 13, may be regulated to also admit a restricted quantity of` air,.or this lower admission of air may be entirely cut oii; so that the fluid rising to the ports 24 may either be mixed liquid and gas or pure liquid. air is introduced at the ports 24, and the column of mixed liquid and -air is then drawn up through the pipe 13 and over into the reservoir 25, where the liquid and air separate, the air being drawn into the engine manifold and the liquid settling into the body of liquid in the reservoir. As the liquid level in the reservoir rises, the iloat 39 is moved upwardly until the valve 36 is again seated, cutting oli the application of suction. immediately the application of suction is cut od, the column ot mixed liquid and air in pipe 13 is arrested in motion and the liquid settles back through the pipe to its normal level. By this action one or more of the por-ts 24 are again uncovered and communication with atmosphere is restored to the reservoir 25 through the pipes 13 and 20.

Now the peculiar function of the plurality -of air ports 24 is this: tq provide for feed of' air into the column of liquid at a point or points lower down in the lifting pipe 13 than would be provided by a single port' (which must be above the highest normal liquid level); and to provide for stages in the column of mixed liquid and air, the column being lighter in the upper stages. This not only provides for eihciency in lifting the liquid-enabling me to lift a long column with a low vacuumf-but also provides for introduction of air into the column of liquid when for 'any reason the liquid level is low; as when the liquid is 1032i7 1n tank 10, or as when the automobile is moving up afsteep ln any case, a certain amount of grade. With these provisions my system is particularly effective; raising fuel a great distance with a comparatively small vacuum; and therefore raising it constantly and uniformly (though intermittently) in spite of variations in the en ine suction.

It will now be seenthat t e air ports 24, located at a poi-nt above the normal level of liquid, perform two functions; one to `admit atmospheric pressure to the liquid in the service reservoir when suction is not being applied and when the atmospheric pressre' iS-needed'to allow the liquid .in the service reservoir to ow out; and theother being to. supply air in stages, at different points, to -v the rising column of liquid in pipe 13 tol facilitate the upward movement of thecolf|- umn. So far as either function of ports 24 is concerned, it ismore or less immaterial whether air is admitted at the lower end of pipe 13; although the admission of some air at the lower end of the pipe may facilitate somewhat the raising of the mixed column of air and liquid-depending upon the position of the lowermost port 2A. The points at which ports 24 make communication depend more or less on the vertical distance through which the liquid is lifted, the variations in this distance due to the causes stated, the amount of suction available, etc.

In Fig. 5 I show the service reservoir 25a constructed in a unit with the carbureter 11a; The service reservoir has the same float 39 operating the valve 36 through the medium of the lever 37 connected with the float. The suction pipe 33 connects in the same manner as before described with the intake manifold 34 of the engine above the throttle valve 35. The carbureter itself may be of any of the usual constructions; embodying vfor instance the liquid nozzle 50 controlled by needle valve 51 and located in the air passage 52 which connects directly with the intake manifold of the engine.

Liquid fuel. is supplied to the nozzle 50 from the fuel chamber 53, which is in communication at 62V with atmosphere. This chamber has no fioat or valve as is ordinarily the case; but may have a float 60 which moves a valve 61 to close an air port 62 when, for any reason, the chamber may be liooded. A horizontal liquid passage 55 may connect the bottom of lreservoir 25a with the bottom of chamber 53; and any suitable check valve, indicated at 56, may be plac in this communication to prevent back ow of liquid from chamber 53 to reservoir 25 when suction is applied to the reservoir 25a. Whenever the liquid level in reservoir 25a is higher than that in chamber 53, liquid will flow from the reservoir to the chamber to replenish the suppl in the chamber. The maximum height o liquid in chamber -53 is level with the maximum height in reservoir 25a; and this maximum height controlled entirely bythe action of float 39 and valve 36; because whenever the valve 36 is closed, it is impossible to introduce liquid into the reservoir by the suction action.

In this last explained form of system, it will be seen that the float 39 Vnot only acts to maintain the level of liquid in the chamber 2 5a but also acts to maintain the level of liquid in chamber 53 and to limit the rise of liquid in that chamber. Consequently, the float 39 performs a double function in that it controls the application of suction to the service reservoir and controls the lifting of liquid from tank 10 and the filling of the reservoir, and also controls the liquid i .level in the chamber '53 which directly and f immediately feeds the carbureter proper, particularly in case where the level of the lherein described, as variations and modifications may be made without departing from my invention. For instance, the exact means of introducing air may be varied. It will be noted that I' explain the introduction of air at 16 at the lower end of the lifting pipe and then explain a different means for introducing air into the lifting pipe above its lower end; but, for all intents and purposes, the admission at 16 is, or may be, substantially the same as admission through the ports 24; so that the port 16 is included within the broad statement of an air admission means below the normal level of liquid in the lifting pipe.

Having described a preferred form ofV my device, I claim: 90

1. In a liquid feed system, the combinationof a liquid tank o'f considerable depth, a liquid reservoir above the tank, a communication between the tank and the reservoir extending to and adapted to draw liquid from said tank throughout a wide range of variation of level of the liquid therein; means to apply suction to the upper part of the reservoir, and means to restrictedly admit atmosphere to said communication simultaneously at vertically spaced points at least one of which is above the liquid level in the tank and others of which are at substantially different depths below said level.

2. In a liquid feed system, the combination of a liquid tank, a liquid reservoir above the tank, a communication between the tank and the upper part of the reservoir, means 'for applying suction to the reservoir, means for discontinuing said suction, and means for restrictedly admitting air to said communication simultaneously at vertically spaced points below the liquid level in the reservoir and at least one of saidpoints being above the liquid level in the liquid tank.

l3. In a liquid feed system, the combination of a liquid tank, a liquid reservoir above the tank, 'a communication between the tank and the reservoir, means for applying suction to the upper part of the reservoir, valve' means in the reservoir for cutting off suction to the reservoir, a lioat for actuatin said valve means, and means for restrictely admitting air to said communication simultaneousl at vertically spaced points below the liquld level in the reservoir and at least one of said points being'above the yliquid level in the liquid tank.

4. In a liquid feed system, the combination of a liquid tank, a liquid reservoir above the tank, a communication between the tank and the reservoir, means for applying suction to the upper part of the reservoir, means for discontinuing said suction, means for restrictedly admitting air to said communication simultaneously at vertically spaced points below the liquid level in the reservoir and at least one of said points being above the liquid level in the liquid tank, and means for restrictedly admitting atmosphere at the lower end of said communication near the liquid tank.

5. In a liquid feed system, the combination of a liquid tank and a liquid reservoir above the tank, a connuunication between the tank and the reservoir, means for applying suction to the upper part of the reservoir. valve means in the reservoir for cutting otl' suction to the reservoir, a float for actuating said valve means, means for restrictedly admitting air to said conununication simultaneousl)Y at vertically spaced points below the liquid level in the reservoir and at least one o'f said points being above the liquid level in the liquid tank, and means for restric-tedly admitting atmosphere at the lower end of said communication near the liquid tank.

6. In combination with a carbureter having a fuel chamber open to atmosphere, a low level liquid fuel tank and a high level service reservoir feeding the carbureter vchamber by gravity, a connuunication between the tank and reservoir, means to apply suction to the reservoir, and means to restrictedly admit atmosphere to said communication simultaneously at verticallyv spaced points one of which is above the liquid level in the communication and others of which are below said liquid level.

7. In combination with a carbureter, a low level liquid fuel tank, a liquid fuel reservoir above the carbureter and in communication therewith to supply it with fuel, a communication between the tank and reservoir, means for restrictedly admitting atmosphere to said communication simultaneously at spaced points one of which is above the liquid level inthe communication and others of which are below said liquid level, and means to apply to the upper part ieiaeie o'f the reservoir the same suction that is applied to the carbureter to maintain a partial vacuum in the reservoir and to draw therefrom the air which enters it with the fuel.

8. In combination with a carbureter having a liquidfuel chamber open to atmosphere, a` low level liquid fuel tank, a high level service reservoir feeding the carbureter chamberby gravity,` a communication between the tank and reservoir, means to restrictedly admit atmosphere to said communication simultaneously at points one of which is above the liquid level in the communication and others are `below said liquid level, and means to intermittently apply to the upper part of the reservoir the same suction that is applied to the carbureter to maintain a partial vacuum in the reservoir and to draw therefrom the air which enters it with the fuel.

9. In combination, a carbureter, a low level liquid fuel tank, an upper reservoir in communication with said low level tank and feeding the carbureter by gravity, means for applying suction to the reservoir, and means for admitting atmosphere to the communication between the tank and the reservoir, said means comprising an air pipe arranged interiorly of said communication and having one end open to atmosphere.

10. In a liquid 'feed system for internal combustion engines, the combination of a liquid tank, a liquid reservoir above the tank, a Communication between the tank and the reservoir, means for applying suction to the upper part of the reservoir, and means for restrietedly admitting air to said communication between the tank and the reservoir, said means comprising an air pipe arranged interiorly and longitudinally of said communication and having one end openA to the atmosphere and having a series of openings along its length through which air may enter said communication.

In witness that I claim the foregoing I have hereunto subscribed my name this 27th day of November 1916.

CHARLES L. STOKES.

Witnesses:

THOMAS H. WEST, BERTHA M. SAVAGE. 

